Ura Dainiji Nyuugakushiken Lanimation -

The title Ura Dainiji Nyuugakushiken refers to a hypothetical or "shadow" version of the rigorous entrance exams for First High School. While the main series depicts the exam results (Tatsuya as a Course 2 student, Miyuki as Course 1), this animation explores the emotional weight of that divide.

It seems you are referring to (裏第二次入学試験), a comedic dōjin (fan-made) anime short based on the The Idolm@ster franchise, often abbreviated as “Ura-nyuu” (裏入試). ura dainiji nyuugakushiken lanimation

Below is a blog post covering its themes, production, and lasting impact. The title Ura Dainiji Nyuugakushiken refers to a